An old radio hand himself, Lamb knew it was a rare opportunity to expand the public affairs network he founded in 1979 that provides gavel-to-gavel coverage of Congress.

C-SPAN put in a bid but came up short. California-based Christian broadcaster Salem Communications outbid the cable network, and the opportunity seemed lost. But the deal was short-lived. Salem ran into a buzz-saw of criticism locally when it announced its plans for the station. It later withdrew its bid. C-SPAN stepped in, purchasing the station for $13 million, and WCSP 90.1 FM was born.

The station went on the air with the long-form format that C-SPAN is known for on Oct. 9, 1997 — Lamb’s birthday.

“He was first on the air that day,” Swain recalled. “It was kind of a special day for him.”

C-SPAN Radio needed to build a schedule, and quickly. One of the first things Lamb did was call the late Tim Russert to see if NBC would be in favor of re-airing “Meet the Press” on the radio on Sunday afternoon. He also reached out to the hosts of the other talk shows: Cokie Roberts, Bob Schieffer, Wolf Blitzer and Tony Snow. All five hosts saw the public-service value and jumped on board. In a matter of weeks, the deal was sealed.

“It was important to have all of them from the beginning … And we never exchanged contracts,” Lamb said.

It’s a common quip that C-SPAN makes great radio because of its long-form style — which some consider boring and unexciting. But C-SPAN is not a news network. It’s a public-affairs network. The radio station is an extension of that mission, and the unfiltered access it provides to the listener has made it the success it is today.

Radio is Lamb’s preferred medium. An information junkie, he listens only to news and talk radio.

“You learn a lot more on radio,” he said. “It’s so much more creative than TV. You can create an image in your mind. You can hear context.”

All told, he listens to about three hours of radio per day. And he doesn’t stop there.

“I go to bed with a plug in my ear,” Lamb said. “It’s how I learned Osama bin Laden had been killed.”

One of C-SPAN’s biggest challenges in the early days was presentation.

“How do we do long-form programming without stepping on it?” Swain said. “The concept of listening … and watching is very different.”

On television, C-SPAN uses announcers to introduce programming and set it in context. But as a rule it does not interrupt its coverage of the House and Senate, hearings or other events to provide analysis, preferring instead to let the programming speak for itself.

C-SPAN television relies heavily on onscreen graphics to identify people appearing on the network, and supplements that with informational graphics to enhance viewers’ understanding of the program they are watching.

Radio doesn’t have those possibilities, so on-air hosts have to help guide the listener and fill in the gaps. Dead air is a not an option.

“The biggest challenge is getting from one live event to another when events don’t start on time,” morning host Nancy Calo said. “You have to keep it interesting and pertinent.”

Unlike C-SPAN television, the radio station does not commit to gavel-to-gavel coverage of Congress or events in Washington. This flexibility in its schedule has allowed WCSP to produce some of its own appointment-listening programs to complement the many events it covers daily. The station goes where the news is in official Washington.

Listeners can find an extensive collection of podcasts online and listen to their C-SPAN app on the go.

Nowhere is this more evident than on its now two-year-old drive-time program, “Washington Today,” hosted by the network’s politics editor, Steve Scully. It airs weekdays between 5 and 7 p.m.

It’s a faster-paced program than the usual long form the C-SPAN audience has come to expect, giving listeners a snapshot of the day or perhaps following an evolving story in real time.

“The goal is for people who are interested in what is happening in Washington, ‘Tell me what happened here today,’ ” Scully said. “ ‘I’m interested in public policy. Give me the facts.’ Listening to the radio program is an extension of the network — ‘Here’s what we covered today. Here’s where you can find it.’ ”

This is relatively new territory for C-SPAN. But Scully, who got his start in local news, enjoys the pace and the freedom the format offers.

“I like news,” he said. “This is an extension of what I used to do. There’s an immediacy with radio, and it keeps me sharp.”

Still, what makes C-SPAN Radio stand out from the crowd is its oral histories and archival programming, in particular the Lyndon Johnson White House tapes.

C-SPAN Radio began airing the tapes in January 1998. There are some 643 hours of recordings, and “almost all that were of suitable quality have been aired,” said Roberta Jackson, who produces the historical segments.

LBJ Library Director Mark Updegrove said C-SPAN Radio’s airing of the tapes “has certainly enhanced LBJ’s reputation and given people a greater appreciation of his legacy. … Nixon’s tapes condemned him. It’s just the opposite for LBJ.”

Although the listener has the benefit of knowing how history unfolded, hearing an American president’s phone conversations can stop listeners in their tracks.

Among the most memorable, Jackson recalls some of the phone conversations from the night of March 31, 1968, the night Johnson announced to the nation that he would not seek the Democratic presidential nomination. Johnson is in his bedroom with Lady Bird, and the calls start coming in late into the night.

Johnson responds, “It’s been made up for a while … That can’t be … That bridge has been crossed.”

“You hear his discouragement,” Jackson said. “Johnson was the ultimate political animal. He wasn’t just giving up his presidency. He was giving up his way of life. Those things strike you as you listen to them.”